Recently, ultra-high-density storage devices using three-dimensional (3D) memory stack structures have been proposed. For example, a 3D NAND stacked memory device may be formed from an array of an alternating stack of insulating materials and spacer material layers that are formed as electrically conductive layers or replaced with electrically conductive layers over a substrate containing peripheral devices (e.g., driver/logic circuits). Memory openings may be formed through the alternating stack, and are filled with memory stack structures, each of which includes a vertical stack of memory elements and a vertical semiconductor channel.